The long-term goal is to provide new and improved analytical methods that will enable researchers to find gene markers genetically linked with the putative gene(s) for schizophrenia. This, in turn, will open the way to identifying the schizophrenia gene(s). Once such genes are found, there is hope that knowledge of their structure will lead to a deeper understanding of the disease etiology and, thus, to the possibility of ameliorating or curing schizophrenia. The specific aims consist of 1) developing and implementing chromosome-based computer simulation, 2) implementing exclusion mapping of schizophrenia under heterogeneity, 3) studying and implementing methods of allowing for biological variables in linkage analysis of schizophrenia, 4) adapting the LINKAGE programs for their use on parallel computers for more efficient linkage analysis, 5) to study the feasibility and power of nonparametric ad hoc statistics for major genes in schizophrenia families, and 7) to consult with and give advice to researchers collecting schizophrenia families and to apply the methods obtained to schizophrenia families (data collected through projects of other investigators). Computer programs and methods obtained through this work will be made freely available to researchers.